Walk the glaring streets of Los Angeles’ San Fernando Valley on a sun-soaked afternoon in a drought year, the dry, brush-covered mountains rising behind you, and it can be easy to feel that you’re in arid country. “Beneath this building, beneath every street, there’s a desert,” said the fictional mayor in the Oscar-winning 1974 movie Chinatown. “Without water the dust will rise up and cover us as though we’d never existed!”

It’s an apocryphal idea. L.A. is not the Mojave but, climatically, more like Athens. Artesian springs, fed by rain in the mountains and hills, used to bubble up around Los Angeles, and farmers and Spanish missionaries grew fruit and olives in the Valley starting in the 18th and 19th centuries.

But the city has a history of treating its own raindrops and rivers as if they were more problematic than valuable. The L.A. River was prone to catastrophic floods in heavy rains, and, in the 20th century, engineers buried, straightened, and paved sections of the riverbed, flushing the water through concrete drainage channels to the Pacific Ocean.

Then, to quench the thirst of its growing population, Los Angeles undertook a series of engineering feats that pumped water from the eastern Sierra Nevada Mountains, Northern California, and the Colorado River via hundreds of miles of pipes and reservoirs. Now the city typically imports more than 85 percent of its water from afar. And it’s as if the waters of Los Angeles disappeared from the consciousness of locals: Many Angelenos will tell you, mistakenly, that they live in a desert.

In the past decade and a half, a few local environmentalists have been collaborating with city and county officials to rewrite the plan for water here, driven by more and more urgent necessity. As winter temperatures rise in an era of climate change, the city’s distant water sources, fed by mountain snowmelt, are becoming less reliable. And drought years and battles over water allocation are adding to the difficulties. The State Water Project, which transfers water from the north to southern California, announced this year it would supply only five percent of the amount of water requested by agencies around the state (including the Metropolitan Water District of Southern California, which supplies parts of Los Angeles), because of the drought. Court rulings to protect endangered species have limited the amount of water L.A. and other cities can take from the Sacramento-San Joaquin Delta.

There’s no easy way for L.A. to get more water from distant sources, but new research from UCLA suggests that rainfall in the Los Angeles region is likely to stay the same on average in decades ahead.

Urban drainage in L.A. can never look like wild creeks, but restoring some capacity to store, slow, and filter water fixes many problems.

The city will need to become more water self-reliant to survive the rest of this century, and capturing local rain looks much more desirable than in the past. “There’s been a refocus on the value of local stormwater as a resource, not as a nuisance,” says Kerjon Lee, public affairs manager for the Los Angeles County Department of Public Works.

During the 1990s, in the flat landscape of Sun Valley, a San Fernando Valley neighborhood at the foot of the Verdugo Mountains, Los Angeles engineers and bureaucrats began re-imagining what one could do with raindrops.

Sun Valley never stopped acting as a tributary of the Los Angeles River, even as many of its lots filled, over the past several decades, with sand and gravel pits, auto body shops, junkyards, metals recycling plants, and miscellaneous blue-collar industries. Now two-thirds of the land here is covered with what engineers call an “impervious surface,” like concrete or asphalt, which water cannot penetrate. The more such surfaces there are in a neighborhood, the more rainwater tends to puddle up and flood. Heavy rain can make many of Sun Valley’s streets impassable. In one of the worst storms, about a decade ago, a sinkhole swallowed up part of a major street that used to be a riverbed, and a city engineer tumbled in and died.

Sun Valley is one of a few areas of L.A. not served by the massive drainage system that sends stormwater either to San Pedro or Santa Monica Bay. In the 1990s, the county planned to build a series of storm drains throughout the neighborhood—until a local environmentalist and gadfly named Andy Lipkis stepped in and asked them to reconsider.

Lipkis founded an organization called TreePeople in the mid-1970s, when he was just a teenager. The organization eventually made its headquarters on the site of an old fire station in Coldwater Canyon Park, on the high ridgeline along Mulholland Drive, named after the famous engineer who designed the first system to import water to the city on a large scale. There, among the breezy, fragrant slopes of oak and bay trees, you can see what Lipkis has been trying to tell locals his whole life: Much of Los Angeles is part forest and part river.

In 1998, Lipkis rigged a south L.A. house with water cisterns and rain gardens, gathered a group of local officials, and staged a deluge, aiming fire hoses at the roof. The group watched with amazement as the lot soaked up thousands of gallons of water.

He convinced them to consider what, at the time, was a more experimental and costly approach to managing water in Sun Valley, which overlies the San Fernando Valley Groundwater Basin, an aquifer that supplies about 13 percent of L.A.’s water. Lipkis argued that the county and city could begin to revive some of the features of a natural watershed.

The urban drainage-ways of Los Angeles can never quite look like wild creeks, but restoring some of their capacity to store, slow, and filter water fixes many problems at once. When stormwater gushes across pavement, it picks up debris and contamination; when it soaks into soil and enters an aquifer, it is cleaner. Conventional storm drains would have only cost about $40 million, while TreePeople says its recommendations were nearly five times as expensive. But the organization’s own analysis suggested that the latter would return at least $300 million in benefits to the city.

Water managers brought the options to stakeholders and residents in the mostly Latino, working-class neighborhood. They chose Lipkis’ approach. “The community didn’t want more concrete,” says Lee.

Alicia Gonzales moved to Sun Valley in 1985, as a nine-year-old, after her parents “fell in love with the house” on Elmer Avenue. Then she and her family watched as the rains poured through her yard, turning it from grass to mud. She remembers how the rain would form a torrent in the alley near her family’s house. “Trash and shopping carts would get stuck there,” she says.

She moved out as a young adult, then returned several years ago to help her father, who was struggling with severe diabetes and kidney disease and needed regular dialysis.

When the streets flooded, many kids in the neighborhood stayed home. Gonzales often wouldn’t drive her daughters to school on rainy days. “My car would get stuck,” she said.

Though Lipkis had sowed the ideas for a new way to manage water here, years passed before anyone found the funding and wherewithal to solve Elmer Avenue’s flooding problems. In 2004, L.A. County finalized a new stormwater plan for Sun Valley. Two years later, the county finished its first project. Under a baseball and soccer field in Sun Valley Park, a tree-lined oasis in the middle of an industrial district, engineers installed a retention tank that collects runoff from the surrounding streets.

In 2007, the county Flood Control District spent nearly $4 million to build drains, catch basins, and a tiny corner park at an intersection that used to turn into a deep lagoon in heavy rain—and was a favorite location for news crews to shoot dramatic footage of local storms.

About eight years ago, employees of TreePeople appeared on Gonzales’ block. They said that her street was part of a watershed, and stormwater from the mountains was pouring into her backyard. (When Gonzales first met Andy Lipkis, she says he rhapsodized about her parents’ olive tree, nearly the only landscaping that had survived the flood damage.) An organization called the Council for Watershed Health had partnered with TreePeople to renovate her street.

These projects have become test cases for boosting the water supply across the entire region.

The Council for Watershed Health led the effort to pull apart the street and put in rain barrels, rain gardens, underground water tanks, and water-permeable walkways and driveways. Gonzales got one of a few special grants to replant her muddy yard, and volunteers showed up at her house to help with the landscaping.

The alley became a pedestrian walkway that the project organizers dubbed The Paseo, a meandering sidewalk lined with native plants between concrete-block walls, painted with the words “Water is the driving force of life.” In rainstorms now, the water runs through the landscaping, and kids walk the path to school. Neighbors water their drought-tolerant plants with rain barrels, but most of the rain soaks in under the street.

As small as these three projects were—a single city block, a corner park, and a soccer field—they have gotten the attention of the entire region: two Southern California regional water districts, several Los Angeles city and county agencies, the federal Bureau of Reclamation, and a number of state agencies got involved and provided funding for Elmer Avenue.

In Sun Valley, the county plans ultimately to capture nearly all of the rainwater that pours through the neighborhood. Next to Sun Valley Park, the city and county are planning to convert what is now a gravel pit and concrete plant into a 46-acre park that will collect in an average year about enough water to supply 4,000 Angelenos.

Their findings come at a crucial time. Crumbling infrastructure and a new court ruling are forcing the hands of local officials: A federal court has ordered the county to clean up the Los Angeles and San Gabriel Rivers, currently fouled by the dirt, grime, and toxins that wash from streets into storm drains. Meanwhile, billions of dollars worth of city water infrastructure is falling apart and has to be replaced before it breaks down.

The city needs to both clean up its stormwater problem and find more water to drink. TreePeople says it could do both at once and is working with the City of Los Angeles to rewrite its entire stormwater management plan by next year. The county has undertaken a study, in partnership with the Bureau of Reclamation, to predict how climate change will affect local hydrology and what it can do to better capture stormwater.

Water districts throughout the region are following suit: The Water Replenishment District of Southern California, which manages groundwater for parts of the region, has set a goal to wean itself off imported water altogether by treating and recycling wastewater and collecting more stormwater. The Council for Watershed Health released a study in 2012 estimating that the district could capture 5.5 billion gallons of water per year through more projects like Elmer Avenue.

The city of Santa Monica has set a goal to use only local water by 2020. The Los Angeles Department of Water and Power estimates that by 2035, it will import just over half of its water (down from 85 percent), meet 9 percent of its water needs by conserving more, and supply 28 percent by using local groundwater, capturing stormwater, and recycling water from sewage.

Water recycling and stormwater projects aren’t cheap, but they’re typically less costly than building high-energy desalination plants that distill water from the ocean. A new desalination plant is going up in Carlsbad, south of Los Angeles. But if groups like TreePeople and the Council succeed, southern California may not need to build many more facilities like this.

“We’re looking at how we could shift the amount of water we currently squander.” says Edith de Guzman, a researcher at TreePeople.

• Madeline Ostrander wrote this article for YES! Magazine. The original article is here. Ostrander is a contributing editor to YES! and a 2014 National Health Journalism Fellow. She lives in Seattle and writes about the environment and climate change.